Archaeologists believe that European civilization began in the Danube basins and the fertile lowlands of Serbia. Happily for visitors, each of the subsequent cultures to dominate the region—Romans, Slavs, Bulgarians, Byzantines, Ottomans, and Austrians—have left their mark in castles, towers, monasteries, bridges, and mosaics, often set among some of the continent's lush green landscapes. The brutality of Serbia's history in the 20th-century, especially in the 1990s, has dampened some travelers' interest. This sometimes leaves millennia old sights wonderfully free of tourist hordes and business development.